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Hypothesis testing

There are multiple hypothesis tests available in Minitab and should be utilized as per data type and the objective.

Let’s take an example of one sample t-test.

One sample t-test

One sample t-test is used to compare population mean with a defined value using sample data.

The test uses sample standard deviation to calculate population standard deviation. If there is a large difference between the sample mean and the specified test mean (given value), then the test concludes that it is highly unlikely that population means will be anywhere near test mean.

Assumptions

1. Sample data follows normal distribution

2. Sample data is random

Analysis in Minitab

Let’s assume sample data of average handling time:

To validate if the goal of reducing population mean to 4 minutes is significant, we can use one-sample t-test.

H0: Hypothesized Mean (4 min) = Population Mean (µ)

H1: Hypothesized Mean > Population Mean (µ)

Step 1: Check if data follows normal distribution to ensure we can use t-test.

To check do to Stat -> Basic Statistics -> Graphical Summary

If p-value is greater than 0.05, that means data follows the normal distribution.